Cooling system for electron discharge devices



July 19, 1949.

W. S. WESCHLER ETAL COOLING SYSTEM FOR ELECTRON DISCHARGE DEVICES Filed June 29, 1946 v IN V EN TORJ'. [MY 2122 (I WeJcfi/er; Roberf 1? 19061 1 6? 690 Richard R Cozyvoran.

AZTORZVEK Patented July 19, 1949 COOLING SYSTEM FOR ELEcrnon DISCHARGE DEVICES William S. Weschler, Camden, Robert P. Roetter,

Westmont, and Richard P. Corporon, .Haddonfield, N. J., assignors to Radio-Corporation, V America, a corporation of Delaware y Application June 29. 1946, SerialNo. 6 80.490

. the device.

In one usual form of cooling system for medium powered vacuum tubes the tube'is seated on the upper edge of an open-ended duct or pedestal with the end of the anode, and its heat radiating fins, presentedto a rapidly moving 6 Claims. (01150-275)- column of air which is introduced through the opening at the bottom of the pedestalj If, as is usually the case, the cooling air impinges upon the end of the anode with substantial force, considerable turbulence is set up adjacent to the said end of the tube. The resulting static air pressure adjacent to the end of the tube not only decreases the cooling efficiency of the system but may also give rise to wind noise and to microphonic disturbances in the electrode structure within the tube.

Accordingly, the principal object of the present invention is to improve the cooling efiiciency and reduce the noise and microphonic disturbances incident to the operation of present day vacuum tube cooling systems, and this too without any increase in the length of the cooling column or in the original velocity of the cooling medium.

The foregoing and other objects are achieved in accordance with the invention by the provision, within the pedestal or cooling duct of the system, of an axially disposed inverted coneshape baiile which serves to direct the cooling fiuid away from the free end of the anode and through the fin structure of the tube in a continuous non-turbulent stream. With the cooling efficiency of the system thus increased it is entirely practical to decrease the length or height of the cooling duct and thereby to provide a more compact installation than is dictated by the prior art.

In the drawing, Figs. 1 and 2 are elevational views, partly in section, showing two alternative embodiments of a vacuum tube cooling system within the invention.

In the drawing, wherein like reference characters designate the same parts in both Figs. 1 and 2, there is shown a conventional vacuum tube I (say an RCA type 827R. or 7024) comprising a bulbous glass portion 3 and a centrally disposed dependent metal portion 5, which latter part comprises the anode of the device. As in standard practice this external anode 5 is provided with amultiplicity. of radially extending-metalfins for dissipating heat generated within the tube I during its operation. As is also conventional the tube is shown supported by its fins l upon avertically arranged hollow cylin drical duct or pedestal 9, wherein the dependent anode 5 and its radiating structure 1 are presented to a cooling stream of airgenerated by a blower II, which is conveniently mounted'beneaththepanel or other base [3 upon which the pedestal 9 stands. The fins 1 will ordinarily extend the full length of the anode 5 but in the drawing the said tube part has, been extended beyond the lower edges of the fins to reveal the structure of that part of the anode which extends across the axis of the pedestal and has heretofore been presented to the air stream. In Fig. 1 the said part or extremity of the anode is shown as a concave surface 5a and, in Fig. 2 is convex, as shown at 51). The anodes of other air-cooled tubes may terminate in a relatively fiat surface.

As previously indicated, the present invention is predicated upon an appreciation of the fact that when the cooling blast is permitted to impinge upon the dependent lower face of the anode, considerable turbulence and a resulting static pressure, is set up thereabouts. To obviate, or at least to minimize, this objection to prior art cooling systems the present invention dictates the use of shield or baflie l5 axially disposed between the blower II and the tube for directing the cooling stream away from the end face (Ea-5b) of the anode outwardly through the cooling fins I and upwardly along the cylindrical side walls of the anode.

In the embodiment of the invention shown in Fig. 1 the shield l5 comprises simply an inverted solid cone made of porcelain, steatite, Bakelite or other suitable insulating material, arranged with the apex of the cone presented to the outlet of the blower H and its base afl'ixed to the concave end 5a of the anode as by means of a screw l5a. In the preferred embodiment of the invention shown in Fig. 2 the narrow lower end of the shield I5 is provided with a number (in this case, four) of radially extending baiiles H which span the opening in the panel [3 through which the cooling air enters the duct or pedestal 9. These baflies thus serve as a support for the cone l5. Furthermore, the presence of these vertically extending plates ll eliminate any eddy currents in the entering air, by preventing circular or lateral flow, within the duct or pedestal 9. Since the end of the anode bulence, wind noise and microphonic disturbances are all minimized.

What is claimed is: a

l. A cooling system for an electron discharge device of the type having a tubularpart to be cooled, comprising a duct through whichia cool ing fluid is adapted to flow, said duct' having'an internal diameter greater than that of said tubular part, means mounting said discharge device within said duct with the end surface of said tubular part extending in a direction trans-- verse to the direction of flow of said cooling fluid, and cone-shaped shielding means within said "duct with the base of the-cone adjacent-said end surface for directing a cooling fluid in a longitudinal path away from said end'surface, whereby to minimize turbulence in the flow of said cooling fl-uicl'adjacent to'said part.

' 2. Incombination; an electron-discharge device having an external anode and .a cooling system therefor comprising an open ended vertically arrangedcylinder in-communicatio'n with a source of cooling fluid,said discharge device being seated on said cylinder, the free end of said anode extending across the vertical axis of said cylinder, and a'cone-shaped shieldmounte'd within said 4 cylinder with the base of said cone-shaped shield in registry with said free end of said anode for minimizing turbulence in the flow of said cooling fluid adjacent said anode.

3. A cooling system for an electron discharge device comprising cooling vanes disposed laterally of a portion of said device to be cooled, a duct for conducting cooling fluid, said vanes extending into said duct, and a cone-shaped member in said duct disposed endwise of said portion and directing the cooling fluid solely to said vanes.

4. The invention as set forth in claim 2 and wherein said shield is supported upon said anode.

5. The invention as set forth in claim 2 and wherein said shield comprises an auxiliary support for said discharge tube.

'6. The invention as set forth in claim 2 and wherein said cone-shape shield is provided adjacent to its narrow end with a plurality of radially extending bailles for minimizing eddy currents in said cooling fluidi 2S. WESCHLER.

ROBERT P. ROETTER.

RICHARD P. CORPORON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name 7 Date 2166;685 Henderson et a1. July 18, 1939 2,324,034 Ski-311B July 13, 1943 v 2,394,396 Mouromtseff et "a1. Feb. 5, I946 

